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611.
Cyclotella ortentalis sp. nov, is described from an epilithic sample taken in Lake Imha, located in Kyungsangbuk-do. South Korea. The species is characterized by a conspicuous and short costa regularly extending from each marginal fultoportula to the valve margin. It can be included in the Cyclotella stelligeroid group. The new species can be separated from the most similar species C. stelligera Cleve et Grunov var. stelligera by the more distant position of marginal fultoportulae from the valve margin, the external long tubes of fultoportulae and having short costae. It differs from C. stelligera var. robusta Must, and var. hyalina Hust., in having much denser marginal striae; from C. glomerata H. Bachm., C. pseudostelligera Hust., C. stelligeroides Must, and C. woltereckii Hust., in its much larger valve, coarser marginal striae and short costae with fultoportulae. 相似文献
612.
Toshikazu Makino 《Microbiology and immunology》1983,27(9):749-755
Protoplasts of Staphylococcus aureus 209P and Cowan 1 were induced by treatment with lysostaphin. These protoplasts were sensitive to detergent, a low concentration of sodium chloride and low temperature. Almost all protoplast cells spread on CLYS agar medium (casein hydrolysate, yeast extract, Na-lactate, and NaCl) formed typical L-form colonies. Horse serum (0.25%) and Mg2+ (109 mm) are essential factors for formation of the L-form colonies of 209P. In the case of Cowan 1, Mg2+ was not required. The active factor(s) in horse serum was heat-resistant and protein in nature. 相似文献
613.
Norio Yamamura Toshikazu Hasegawa Yosiaki It 《Evolution; international journal of organic evolution》1990,44(5):1346-1357
Infanticide has recently been observed in several primate species while female counterstrategies are seemingly rare. The question of why mothers do not increase their resistance to infanticide is investigated using a haploid two-locus model. A hypothesis that mothers can recover lost offspring by gaining more grandchildren is rejected in most cases, and it is shown that costs and benefits for both males and females have the strongest influence on the evolution of infanticide and obedience to it. An estimation of parameters for a natural population of hanuman langurs suggests that infanticide is more advantageous than noninfanticide and the costs of resistance, compared to obedience, is higher than its benefits. Data from other studies on primate infanticide are discussed in the light of results of the model. 相似文献
614.
Toshisada Nishida Junichiro Itani Mariko Hiraiwa Toshikazu Hasegawa 《Primates; journal of primatology》1981,22(4):557-563
A very isolated population ofColobus angolensis has been newly discovered in Tanzania. The monkey has white, long epaulettes and cheek hair, but no white pygal band. Its
tail has somewhat of a brushy tip, and is grey in color. This may very well be a heretofore undescribed, and distinct subspecies. 相似文献
615.
616.
Toshikazu Yamanouchi Nobuyuki Ogata Tomoe Yoshimura Tae Inoue Eri Ogata Takahiro Kawasaki Akiko Kashiwabara Hirono Muraoka 《Biochimica et Biophysica Acta (BBA)/General Subjects》2000,1474(3):291-298
The uptake of 1,5-anhydro-D-glucitol (1,5-AG) occurs by passive mechanisms in cells or tissues that have passive glucose transporters. It is known that serum 1,5-AG concentrations are reduced in patients with diabetes mellitus. To elucidate the metabolism of this substance and its physiological role in pancreatic β-cells, we assayed 1,5-AG transport in the insulinoma-derived cell lines, RINr and MIN6. Both cell lines showed an insulin-insensitive, concentration-dependent uptake of 1,5-AG with a saturation time of approximately 120 min, and most of the 1,5-AG in the cytoplasm was in the free form. A biphasic saturation curve was obtained using a wide range of 1,5-AG concentrations, suggesting that accumulation was mediated by a high affinity and a low affinity transporter. The high affinity transporter had a Km of 10.4 in RINr cells and 13.0 mM in MIN6 cells, and the low affinity transporter had a Km of 131 in RINr cells and 211 mM in MIN6 cells. Uptake of 1,5-AG was markedly inhibited by phloretin and cytochalasin B, but was only slightly affected by phloridzin. Uptake of 1,5-AG was markedly inhibited by glucose at physiological concentrations (1.0–10 mM), as well as by galactose and mannose. The 1,5-AG concentration required to inhibit 2-deoxyglucose uptake exceeded that of glucose by >100 times, being much higher than the physiological concentrations of 1,5-AG. These results indicate that the 1,5-AG carrier system in insulinoma cells is distinct from that in either the somatic cells or renal tubular cells. These findings also suggest that a unique 1,5-AG transport system is present in pancreatic β-cells. 相似文献